Electronic commerce enables computer users to purchase items, such as products and services, on the World Wide Web in a variety of ways using their computers. For example, opportunities to purchase items online include: online stores that are analogous to brick and mortar stores selling large inventories of items at a fixed price, online classifieds that sell a single item at a fixed price, online auctions in which users bid on an item, online reverse auctions in which sellers bid to sell an item to a user, and online purchase aggregation, in which groups of users aggregate their orders for products.
It can be useful for users to be able to identify similar purchasing opportunities, such as different opportunities to purchase the same or similar items. In the case of one-at-a-time purchasing opportunities such as online classifieds, a user may wish to find additional opportunities to purchase the same item where the user needs more than one of the item. For all kinds of purchasing opportunities, a user may wish to (a) price-shop for the same item, or (b) identify similar items that the user might also wish to purchase, either as an alternative to the first item or in addition to it.
Unfortunately, purchasing opportunities are generally not well-organized with respect to these objectives. Indeed, it is common for purchasing opportunities to be organized into general item categories, such as “office supplies” vs. “kitchen implements.” In some cases, purchasing opportunities are not organized at all.
Accordingly, a technique for automatically identifying opportunities to purchase similar items on the World Wide Web would have significant utility.